Automatic pirn changer for a loom

ABSTRACT

An automatic pirn changer for replacing an almost runout pirn in a shuttle by a full pirn in which the yarn or wire from the full pirn is joined to that part of the residual yarn or wire from the runout pirn extending to the shuttle eye at the inside of the shuttle whereupon the join is drawn through the shuttle eye before weaving is recommenced.

United States Patent Inventor Appl. No. Filed Patented Assignee AUTOMATIC PIRN CHANGER FOR A LOOM Primary Examiner-James Kee Chi 9 claims, 5 Dumas m AnomeyBeveridge & De Grandi U.S. 139/224,

139/259 ABSTRACT: An automatic pirn changer for replacing an al- Int. 'D03d 45/00, most runout pim in a shuttle by a full pim in which the yarn or D03d 45/02 wire from the full pim is joined to that part of the residual yarn Field of Search ..139/2 5 6-261, or wire from the runout pirn extending to the shuttle eye at the 246-248, 242, 243, 244, 224, 380; inside of the shuttle whereupon the join is drawn through the 289/2.3 shuttle eye before weaving is recommenced.

1: Q f. x N a PATENTED SEP28 I97! 31508589 sum 1 or 5 INVENTOR;

PAIENIEB SEP28 lsm 3608589 sum 3 or 5 SHEEI 5 BF 5 AUTOMATIC PIRN CHANGER FOR A LOOM This application is a continuation in part of my pending ap plication Ser. No. 723,818 now abandoned.

In a known automatic pirn changer for a loom for weaving textiles,the yarn extending fromthe cloth to the shuttle is cut near the shuttle and the runout pirn is removed from the .then cut off by cutters (selvedge cutters) located adjacent to the cloth.

Such an'automatic pirn changer cannot housed on wire weaving looms. and on some synthetic textile yarn and monofilaments because shuttle with open eyes are not satisfactory for these materials.

The present invention provides an automaticpirn changer for replacing, an almost run out pirn carried within a shuttle having aclos ed, eye by a full pirn, comprising means for extracting the almost runout pirn from the shuttle, means for effecting a joinbetween theyarn on the gull pirn and that part of the residual yarn from the runout pirn extending from the shuttle eye at the inside of the shuttle, and astripper for draw.- ing said join through the shuttle eye beforeweaving is recommenced.

. Preferably a transfer. head is provided for extractingthe almost runout pirn from the shuttle and inserting the full pirn.

Advantageously, o the transfer head is adapted to move between at least two angularly spaced apart, fixed positions, in a first of which it ispositioned forgrippingapirn in the shuttle when the latter isstationary, substantially beneath ,the transfer head. Conveniently, thetransfer headhas a thirdfixed position angularlydisplaced from said first and second positions.

The joiningmeans preferably comprises a knotter which is adapted to firstly receive at least a portion ofthewireextending from the almost runout pirnto the shuttle eye when this pirn is moved by. the. transfer head between said first and second positions, and secondly to receive a portion of the wire,

extending from a full pirn when this pirn.is moved bythe transfer head between said third andfirst positions.

The stripper is adapted to draw. off the remaining wire from said almost runout pirn when the latter has been'extracted from the shuttle and placed in said second position.

The inventionwillibe further described, byway of example, with reference to the-accompanying drawings, in which:

, FIG. 1 is a diagrammatic perspectiveview of one embodiment of a pirn changing mechanism constructed according to the present invention showing an almost empty pirn having been brought to rest beneath thetransfer head;

FIG. 2, is a viewsimilar to that of FIG. 1 showing the almost empty pirn in the rewinding position;

FIG. 3 is a view similar to that of FIG. 2 showing a full pirn having been transferred by the transfer head to the empty shuttle; V

FIG. 4 is a perspective view of a part of a loom adapted to receive the pirnchangingmechanism of FIGS. 1 to 3 showing the pivotable forked lever for threading the stripper in detail but with the other partsof the mechanism removed for clarity; and

FIG is a block diagram illustrating theoperation of a control circuit for the pirn changing mechanism ofFIGS. l to 4.

With referenceto the drawings, partof a standard loom for weaving wire is shown in FIG. 4, those parts of the loom not shown having been well known to those skilledin the art for at least the last 50 years. Theloom hasbeenmodified by the addition of the pirn changing mechanism illustrated diagram matically in FIGS. 1 to 3, although'most of this mechanism has been omitted from the view of FIG. 4 for clarification purposes.. I

The loom has a shuttle 1 whichis passed between two shuttle stations on a raceboard 2, onlythe left-hand shuttle station being shown in FIGS. 1 to 4. The shuttle. is projected from each v shuttle station by a respective picking stick 1201A transfer head 3 (FIGS. 1 to 3) is mounted on a changer frame 34 which is suspended froman extended loom bridge 122 (FIG. 4) above the left-hand shuttle station. The transfer head 3 is rotatable about a horizontal axis into one of three angular positions as will be further described below. 1 1

The shuttle is adapted to hold a pirn 4 which carried a coil of wire (shown by a solid line in FIG. 1) for the weaving process. The wire extends from the pirn4 over a first pulley 6, and a second pulley 7 to the cloth 124 (FIG. 4) being woven.

A stripper 29 is located adjacent theshuttle station illustrated and comprises a rotatable disc 30 having a plurality-of rods 31 extending axially therefrom and angularly displaced from one another around the disc. A pivotable forked lever 101 is arranged for engaging the wire extending between the shuttle when at the left-hand station and the cloth- 124, and loopingit over the rods 31. The forked lever 101 is pivotable about a pivot 103' by. means of an actuator 104 so that its shaped tip-102 moves obliquely across the front of the stripper 29. When actuated, the forked lever 101 moves in the direction of arrow A (FIG. 4) so that the shaped tip 102 rides over the wire extendingfrom the shuttle pulley 7 to the cloth being woven. On the return of the forkedlever 101 to the position illustrated, the wire extending from the shuttle pulley 7.to the cloth 124 is caught in a notch 126 in the shaped tip 102 of the lever 101 anddrawn over and between the-rods 31.

Subsequent rotation of the disc 30wraps the wire around the rods simultaneously pulling down the lever 101' in the direction of the arrow A" against a reducing pressure in the actuator'104. After approximately three revolutions of the disc 3 0, the shaped tip-102'ofthe lever 101 has been drawn down to approximately the level of the center of the disc 30and an actuator l07=isoperated to rotate a fork ab outa pivot 106 which is arranged-torelease the wire from the notch 126. The lever 101 isthusfreed from the, wire and returns to its illustrated rest position to await the next signal indicating that a further pirn changing operation is to be effected.

Further rotation of the-disc 30., in the same sense as above, winds off wire frornthe corresponding pirn. A-clamp 30 (not shown in FIG. 4.) located between the stripper 29 and' the cloth is arranged to embrace the wire which extends from the cloth'to thestripper to enable the wire to beclamped during stripping. During normal operation of the loom, the forked lever 101 is inoperative and remains in the position illustrated in FIG. 4..

The transfer head 3 has jaws 8 comprising a fixed jaw 9 and apneumaticallyvoperable jaw 10, the jaw l0 having a groove 1'] adapted to engage a corresponding flanged bracket-28 on a pirn 4, whereby the-pirn 4 may be picked up by the transfer head 3. In order to withdraw the pirn 4-from the shuttle, the shuttle l is displaced axially about the pirn 4which is held by the transfer head 3. The jaws Bare lowered relative to the transfer head 3 by a pneumatic ram 12 and guides 13.

The transfer head 3 is rotatable by pneumatically operable means 14 on the changer main frame 34 and has three fixed angular positions, the lowestof these positioning the jaws 8 adjacent the shuttle ,1. The transfer head is rotated through approximately to reach the second fixed position. A chuck 44 on the changer main frame 34 and a displaceable center 16.

are adapted to receive a pirn presented thereto by'th'e jaws of the transfer head. The clutch 44 may be rotated by an air motor, in one direction, for rewinding an empty pirn gripped thereby, and in the reverse direction for stripping.

The third angular position of the transfer head lies approximately 20 ahead (clockwise in the drawings) of the second position. Displaceable centers 17' and 48" are adapted to receive a pirn presented thereto bythe jaws on the transfer head when the latter is in its second position. This second position is for storing a full pirn ready'to be placed inthe shuttle.

A knottingmechanism 18 is located on a bar 19 fixed-to the changer main frame 34 and comprises a pair of guides 20, a

pair of pulleys-2lvan d a hooked bar 22. The hooked bar 22 may be rotated by a mechanism 23 for knotting wires presented to its hook 43.

A feeler bar 24 is located adjacent the knotting mechanism 18. The function of the feeler bar 24 will be described below.

A further arm (not shown) mounted so as to be parallel to the arm 25 has a clamp 26 and scissors 27 pivotably carried thereby for cutting the wire extending above the knotting mechanism 18 when a knot has been made.

.The automatic print changer is electro/pneumatically powered and controlled, and is independent of the loom drive.

In order to initiate a pirn changing operation of a detector of the well-known Leopfe type is provided on the loom adjacent the right-hand shuttle station, as illustrated diagrammatically in FIG. 5. The pirns used with the loom are provided with a reflective coating 114 on a portion of the pirn normally covered by the coiled wire, so that the reflective coating is only exposed when the wire has been used up, or almost used up, on that pirn. This condition is detected by the detector 108 and a signal appears on the line 130 to control box 132.

The control box 132 contains a relay 134 whose contacts are arranged to connect a line 136 to a positive voltage supply terminal 138 when the detector 108 has been actuated. The line 136 is connected via a switch and a relay coil 142 is a clutch/brake control unit 148 to a negative terminal 144 ofthe voltage supply. When current flows through the relay coil 142, an electrically operated clutch in the loom drive is actuated to inhibitithe weaving function of the loom and bring the shuttle to a halt when it next reaches the left-hand station. The switch 140 is actuated by a rotatable cam 146 attached to the loom drive on the side of the clutch not driven by the power source of the loom drive. The can 146 is orientated and arranged so that it opens the switch 140 at the correct instant to ensure that the shuttle is brought to a halt when at the left-hand station. In fact this switch is closed once every normal cycle of the loom but it only activates the clutch when the detector 108 has itself been actuated.

One side ofa further cam operated switch 150 is connected to the side of the switch 140 connected to the relay soil 142, the other side being connected to a controller 154 for the other pirn changer functions, such as the actuation of the actuator 104 for the forked lever 101. The switch 150 is closed by a rotatable cam 152 attached to the loom drive in a similar manner to the cam 146 but arranged to close its respective switch shortly after the cam 146. This ensures that the shuttle has come to rest at the-left-hand shuttle station before a pirn changing cycle is initiated. The controller 154 for controlling the pirn changing cycle is constructed in accordance with well known techniques used in the art of electro/pneumatic control systems and need not be described further.

A cycle of operations will not be described.

When the wire on the pirn 4 carried by the shuttle 1 has almost been used up by the weaving process, the Leopfe detector 108 is actuated which changes over the relay 134 to activate switch 140. When next the cam 146 closes the switch 140, the clutch and brake unit 148 is actuated to bring the shuttle 1 to rest at the left-hand station beneath the transfer head 3 and in the position shown in FIG. 1. The cam 152 closes the switch 150 when the shuttle is in this position, thus activating the changer controller 154.

The forked lever 101 is actuated by the controller 154 to draw a loop of wire onto the stripper 29 in the manner described above, the wire being clamped by the clamp 39. The stripper 29 is rotated by approximately three revolutions to provide sufficient slack wire for the pirn 4 to be placed between the centers 16 and 44.

The transfer head 3 is rotated to its lowest position, position one, and its jaws 8 are lowered to engage the flanged bracket 28 on the pirn 4. The gripped pirn 4 is held stationary and the shuttle is slightly displaced axially around the pirn from the shuttle.

The jaws 8 are then retracted toward the transfer head 3, thereby withdrawing the pirn from the shuttle 1. The transfer head moves to its upper position carrying the almost empty pirn 4 with it. The pirn 4 is placed between the chuck 44 and the inner 16 in a rewind position (see FIG. 2) The transferring of the pirn to the rewind position automatically draws the wire through the knotting mechanism 18 and over the feeler bar 24. The stripper 29 is rotated to draw off the remaining wire from the pirn 4, until the loose end just extend through the knotting mechanism the wire being held by the guides 20. This condition is detected by the feeler bar 24 which is arranged to inhibit further rotation of the stripper.

The transfer head is rotated to its third position where it picks up a full pirn 25 (FIG. 3) which has been previously wound and then is further rotated to bring the full pirn adjacent to the shuttle 1. The jaws 8 of the transfer head are lowered to place the full pirn 35 into the shuttle, the pirn 35 being moved axially within the shuttle so that the outstanding lugs thereon engage the cooperating member 36 which rigidly supports the pirn within the shuttle. The jaws 8 are opened to release the pirn and retracted towards the transfer head which is rotated back to its third position.

The transferring of the full pirn 35 from between centers 17, 48 to the shuttle 1 is arranged to draw the wire (shown dotted in FIG. 3), which extends from the full pirn 35 to a supply spool (not shown), through the knotting mechanism 18, so as to lie adjacent to the loose wire end already held therein. The wire end which extends from the knotting mechanism 18 to the supply spool is arranged to pass through the scissors 27 and to be firmly held by the clamp 26. The knotting mechanism 18 is then actuated, the hooked rod 22 being axially rotated so as to engage the two wires embraced by the tool 43 to thereby knot the wires together. The scissors cut the wire extending therethrough and the stripper is again actuated to draw the knot from the knotting mechanism 18, over the shuttle pulleys 6 and 7 so as to be clear of the shuttle 1.

On completion of this cycle, the controller 154 provides a signal to the clutch/brake control unit 148 to reconnect the loom drive so that the weaving process recommences.

The clamp 26 is arranged to guide the loose supply wire end into a notch on the empty pirn 4 held between the chuck 44 and center 16. Rotation of the chuck 44 causes the pirn 4 to be rewound from the supply, balanced winding being obtained by a slidable guide 38. On completion of the rewinding operation, the nowfull pirn 4, is transferred to the position between the centers 17, 48 to await the restart of the cycle.

The wire extending from the cloth to the clamp 39 and the wire extending form the cloth to the stripper are both cut by scissors located adjacent the cloth on arrival at the scissors or cutter.

Alternatively, the transfer head may include a magnetic pickup for carrying the pirn between the three aforementioned positions of the transfer head.

Furthermore, it is envisaged that the stripper 29 might comprise one or more pairs of nip rollers in place of disc 30 and rods 31.

It is to be noted that the basic operation of the print changer described above is fundamentally different from the known automatic pirn changers mentioned initially in which the yarn extending from the cloth to the shuttle is cut outside of" the shuttle, that is between the shuttle and the cloth, and the runout pirn is removed from the shuttle, thus unthreading the shuttle eye. In the known changer, the new pirn is then inserted in the shuttle with the end of its yarn held in a clamp, the shuttle eye being open so that when the shuttle makes its first stroke with the new pirn, the weft yarn is automatically drawn into the shuttle eye.

In a pirn changer according to the present invention the join is made at the inside" of the shuttle, that is, the wire, which is joined to the wire on the new full pirn, is already threaded through the shuttle eye when the join is effected, the shuttle eye being a closed eye. The join is then drawn through the eye to the outside" of the shuttle before weaving is recommenced.

The pirn changer is thus most suitable for those types of yarn, such a metallic wire, which can not be satisfactorily used with a self-threading open eye type shuttle.

I claim:

1. In an automatic pirn changer for replacing an almost runout print carried within a shuttle having a closed eye by a full pirn, means for extracting the almost runout pirn from the shuttle, means for effecting a join between the yarn on the full pirn and that part of the residual yarn from the runout pirn extending from the shuttle eye at the inside of the shuttle, and a stripper for drawing said join through the shuttle eye before weaving is recommenced.

2. A pirn changer according to claim 1 in which a transfer head is provided for extracting said almost runout print from the shuttle and inserting said full pirn, before said join is effected.

3. A pirn changer according to claim 2 in which the transfer head is adapted to move between at least two, angularly spaced-apart fixed positions, in a first of which it is positioned for gripping a pirn in the shuttle when the latter is stationary, substantially beneath the transfer head.

4. A print changer according to claim 3 in which means are provided at said second position of the transfer head for receiving the almost empty pirn.

5. A pirn changer according to claim 4 in which the transfer head has a third fixed position angularly displaced from said first and second positions.

6. A pirn changer according to claim 5 in which means are provided at said third position of the transfer head for supporting said full pirn prior to its insertion into the shuttle.

7. A pirn changer according to claim 6 in which said means for effecting said join comprises a kno'tter which is adapted to firstly receive at least a portion of the yarn extending from the almost runout pirn to the shuttle eye when this pirn is moved by the transfer head between said first and second positions, and secondly to receive a portion of the yarn extending from said full pirn when this is moved by the transfer head between said third and first positions.

8. A pirn changer according to claim 7 in which the stripping means is adapted to draw off the remaining yarn from said almost runout pirn when the latter has been extracted from the shuttle and placed in said second position, and a detector is provided for deactivating the stripper when the end of said remaining yarn has left the now empty pirn, such that an end portion of the yarn lies within the knotter.

9. A pirn changer according to claim 2 in which the transfer head is provided with pneumatically operable jaws adapted for gripping a pirn. 

1. In an automatic pirn changer for replacing an almost runout pirn carried within a shuttle having a closed eye by a full pirn, means for extracting the almost runout pirn from the shuttle, means for effecting a join between the yarn on the full pirn and that part of the residual yarn from the runout pirn extending from the shuttle eye at the inside of the shuttle, and a stripper for drawing said join through the shuttle eye before weaving is recommenced.
 2. A pirn changer according to claim 1 in which a transfer head is provided for extracting said almost runout pirn from the shuttle and inserting said full pirn, before said join is effected.
 3. A pirn changer according to claim 2 in which the transfer head is adapted to move between at least two, angularly spaced-apart fixed positions, in a first of which it is positioned for gripping a pirn in the shuttle when the latter is stationary, substantially beneath the transfer head.
 4. A pirn changer according to claim 3 in which means are provided at said second position of the transfer head for receiving the almost empty pirn.
 5. A pirn changer according to claim 4 in which the transfer head has a third fixed position angularly displaced from said first and second positions.
 6. A pirn changer according to claim 5 in which means are provided at said third position of the transfer head for supporting said full pirn prior to its insertion into the shuttle.
 7. A pirn changer according to claim 6 in which said means for effecting said join comprises a knotter which is adapted to firstly receive at least a portion of the yarn extending from the almost runout pirn to the shuttle eye when this pirn is moved by the transfer head between said first and second positions, and secondly to receive a portion of the yarn extending from said full pirn when this is moved by the traNsfer head between said third and first positions.
 8. A pirn changer according to claim 7 in which the stripping means is adapted to draw off the remaining yarn from said almost runout pirn when the latter has been extracted from the shuttle and placed in said second position, and a detector is provided for deactivating the stripper when the end of said remaining yarn has left the now empty pirn, such that an end portion of the yarn lies within the knotter.
 9. A pirn changer according to claim 2 in which the transfer head is provided with pneumatically operable jaws adapted for gripping a pirn. 